From 1213f5d091b73d5dfc2c53f715f2280d5ff0c291 Mon Sep 17 00:00:00 2001
From: tom-englert <mail@tom-englert.de>
Date: Thu, 16 Jun 2022 17:53:59 +0200
Subject: [PATCH] Add failing test to reproduce #859

---
 Test/Mono.Cecil.Tests/ImageWriteTests.cs | 44 ++++++++++++++++++++++++
 1 file changed, 44 insertions(+)
 create mode 100644 Test/Mono.Cecil.Tests/ImageWriteTests.cs

diff --git a/Test/Mono.Cecil.Tests/ImageWriteTests.cs b/Test/Mono.Cecil.Tests/ImageWriteTests.cs
new file mode 100644
index 000000000..a73da2e14
--- /dev/null
+++ b/Test/Mono.Cecil.Tests/ImageWriteTests.cs
@@ -0,0 +1,44 @@
+using System.IO;
+using System.Linq;
+using NUnit.Framework;
+
+namespace Mono.Cecil.Tests {
+	[TestFixture]
+	public class ImageWriteTests : BaseTestFixture {
+
+		[TestCase("EmbeddedPdbTarget.exe")]
+		// [TestCase("ExternalPdbDeterministic.dll")]
+		public void MultipleWriteOperationsShouldReturnSameOutput (string testee)
+		{
+			TestModule (testee, module => {
+				Assert.IsTrue (module.HasDebugHeader);
+
+				const int numberOfStreams = 5;
+
+				MemoryStream Write(int _)
+				{
+					var stream = new MemoryStream ();
+					module.Write (stream, new WriterParameters { WriteSymbols = true });
+					return stream;
+				}
+
+				var streams = Enumerable.Range (0, numberOfStreams)
+					.Select (Write)
+					.ToArray ();
+
+				static bool AreStreamsEqual ((MemoryStream First, MemoryStream Second) pair)
+				{
+					var buffer1 = pair.First.GetBuffer ();
+					var buffer2 = pair.Second.GetBuffer ();
+					return buffer1.SequenceEqual (buffer2);
+				}
+
+				var results = streams.Zip (streams.Skip (1))
+					.Select (AreStreamsEqual)
+					.ToArray ();
+
+				Assert.That (results, Is.EquivalentTo (results.Select (_ => true)));
+			});
+		}
+	}
+}
\ No newline at end of file